As promised, here’s the second of three excerpts from Chris Green’s Sanctifying Interpretation: Vocation, Holiness, and Scripture (pp. 71–73):
Christian theologians commonly use ‘holiness’ to name whatever it is that makes God different from all that is not-God. Jean-Luc Marion, for example, says that ‘God is distinguished from the world and from other gods insofar as he is “majestic in holiness, terrible in glorious deeds” (Exod. 15:11)’. God reveals himself to creation in such a way that no one can enter ‘the vicinity of his holiness, which separates him from any other [tout autre] as the Wholly Other [Tout Autre]’. Dumitru Staniloae offers a similarly typical account:
Holiness can be said to reveal to us all the divine qualities in a concentrated way. It is the luminous and active mystery of the divine presence. In it there is concentrated all that distinguishes God from the world.
Such descriptions, true so far as they go, are finally insufficient. John Webster is right: ‘God is what God does’; therefore, ‘God’s holiness is to be defined out of God’s works’. Given that Jesus is the full embodiment of all God’s works, we have to look to Jesus and his storied witness of God if we want to know what holiness means. Jesus just is, in himself, ‘the event of the coming of that holiness which crosses the great divide …’ ‘What he does and what is done to him—his whole life history—is … the manifestation of holiness.’
What do we find when we look to Jesus to see God’s holiness? Again, I agree with Webster: we find that holiness is ‘a mode of relation’. It is, in fact, the mode of relation God enjoys as Father, Son, and Spirit—the very mode of relation God opens to us as creatures. God’s holiness is the freedom made possible because Father, Son, and Spirit exist for, in, and with each other. Or, to put it the other way around, because God is holy and in goodness shares that holiness with all things, God is the God God is, and we are the creatures we are, in our life together with God and before God in the world.
All that to say, God is holy in that God relates (both immanently and economically) in ways that are simultaneously free and freeing, lively and life-giving, just and justifying. Because God is holy, we can experience goodness, truth, and beauty in relationship with God in ways that make us good and true and beautiful. To narrow it to a single statement: God’s holiness is the way God has of relating to us so that we can not only know God, but in knowing, become like God. Because God is holy, God can be with us, the ‘holy one in our midst’, not unmaking our humanness but perfecting it, drawing us into humanizing deification. As Keen says, ‘God’s holiness is a freedom for what is far gone from holiness’.
 Jean-Luc Marion, ‘The Invisibility of the Saint’, Critical Inquiry 35.3 (Spring 2009), pp. 703–10 (708).
 Dumitru Staniloae, The Experience of God Vol. 1: Revelation and Knowledge of the Triune God (Brookline, MA: Holy Cross Orthodox Press, 1994), pp. 222–23.
 John Webster, Holiness (London: SCM Press, 2003), p. 39.
 Michael J. Gorman, Inhabiting the Cruciform God: Kenosis, Justification and Theosis in Paul’s (Grand Rapids: Wm. B. Eerdmans, 2009), p. 113.
 Craig Keen, After Crucifixion: The Promise of Theology (Eugene, OR: Cascade Books, 2013), p. 94.
 Keen, After Crucifixion, p. 94.
 Webster, Holiness, p. 5.
 It is opened to us through the ‘communication of attributes’ in Christ. That is to say, the divine holiness, brought to bear by the Holy Spirit, holds the divine and human natures together in Christ without confusion, division, change, or mixture so that the human is healed, perfected, and transfigured by the divine. Holiness not only preserves the integrity of the two natures but also effects the deification of human nature through its ‘contact’ with the divine in Christ through the Spirit. As Veli-Matti Kärkkäinen, expounding on theology of Gregory Palamas, explains in his One with God: Salvation as Deification and Justification (Collegeville, MN: Unitas, 2004), p. 28, ‘When the Logos of God took on human nature, he bestowed on it the fullness of his grace and delivered it from the bonds of corruption and death. They consequence of this hypostatic union of the two natures in Christ was the deification of the human nature’. Similarly, Douglas Harink (1 & 2 Peter [BTC; Grand Rapids: Brazos, 2009], p. 144) says that ‘our human nature is purified and taken up, through our participation in Christ’s humanity (made possible by his participation in ours), into the divine life and fulfilled in its humanity, through that participation’.
 See Webster, Holiness, pp. 5, 9, 43, 45.
 Craig Keen, ‘A Quick “Definition” of Holiness’ in Kevin W. Mannoia and Don Thorsen (eds.), The Holiness Manifesto (Grand Rapids: Wm. B. Eerdmans, 2008), p. 238.